Our national anthem is 250 years old and, from the way it is often played, the poor dear must be feeling its age. Not all the blame for this variable performance quality can be laid at the door of execrable musicianship; it's as much to do with the daunting profusion of arrangements on offer and the fact that scholars and, more importantly, conductors, can't seem to agree as to which is the definitive version. Embarrassing, isn't it? Worse still, nobody's quite sure who wrote the thing. All we know for certain is that its first reported performance took place in 1745 as part of a show of solidarity with George II, pretty much a knee-jerk reaction to the activities of Bonnie Prince Charlie. Clearly there was a North- South divide even then.

Born into a world of conflict, "God Save..." has never since been far from the centre of controversy. The debate over just how it should be played has tormented better musical brains than ours. It even prompted a spate of correspondence between the then Doctor Adrian Boult and Sir Edward Elgar in his capacity as Master of the King's Musik (sik, sorry, sic). The main point at issue is whether one should opt for what we'll call, for convenience, "the straight ending", or launch outlandishly into what musicologists the world over know as "the fancy one". Even after blundering through the BBC's written archives, I'm still none the wiser as to Elgar's view since he appears to have written his reply to Boult with the blunt end of his baton.

Perhaps this fluidity is just as well. Without it, eager record buyers would have been deprived of the torrent of free interpretations by the likes of Peter Cook, Malcolm McLaren and Jonathan King; everyone from the dead to the undead to the don't-you-just-wish-he-was-dead? There's an air of inevitability about the fact that a version exists of "God Save the Queen" by Michael Fagin, the man who committed the ultimate indiscretion: he entered a lady's boudoir without knocking. Jimi Hendrix pledged his allegiance to two flags by recording our anthem as well as his own, "The Star-Spangled Banner": it's a rare musician who can stand to attention while playing the guitar with his teeth.

However, the most unexpected connection between national anthems and the happy-go-lucky world of rock'n'roll becomes horrifically evident during the first few bars of Libya's theme tune. Anyone who has ever heard Gilbert O'Sullivan's "Ooh Wakka Doo-Wakka Day" will find it impossible to avoid singing "I want to tell, I might as well do, About a girl, Met back in May", as Colonel Gaddafi's supporters maintain a dignified silence. To be a Libyan patriot and an O'Sullivan fan must present the ultimate conflict of loyalities.

Like most nationalistic pieces, including our own, the Libyan song is positively caked in bellicosity. Skim through the anthems of the world songbook and you'll find it reads much like the directions in a Schwarzenegger screenplay. References to spilt blood and cut throats abound, to say nothing of "scatter our enemies" (that one's in ours and it was Queen Victoria's favourite bit). Not a lot to smile about, unless you count the "Ooo, er, missus" factor in the first line of the Egyptian anthem, "Oh my weapon, how I long to clutch thee".

Rewriting the lyrics to avoid embarrassment is an option open to the Egyptians but not to the people of Mexico, where an official decree forbids any alterations. Luckily for Leonid Brezhnev, no such edict existed in Russia, so he was able to remove from the Soviet anthem the one word guaranteed to cause maximum offence: Stalin. In Iran, they went further and ditched the whole damn thing. Well, it was called "Long Live the Shah" and these days that's neither relevant nor factually accurate. Despite the best efforts of the Not the Nine O'Clock News team and Richard Stilgoe, both of whom penned ditties in honour of Ayatollah Khomeini, no replacement has ever been adopted. The way is therefore clear for Cat Stevens' attempt.

If Britain were anthemless too, apart from some rather awkward silences before the FA Cup Final and during the Trooping of the Colour, the main effect might be the arrival of a smug, if posthumous, smile on the face of George Orwell who opined more than 50 years ago that "not to have a national anthem would be logical". Did he, perhaps, have some ghastly premonition of the impending Jonathan King cover version?

Bob Sinfield's history of the national anthem, `Ma'am They're Playing Your Song', is transmitted on Radio 2, 9.03-10pm Tuesday 21 Feb